Maxtor has spun out a 100GB hard drive aimed at a small but growing audience of audio and video fanatics. The $300 (about £200) DiamondMax D536X, released Monday, is the latest high water mark for an industry in which technology is butting heads with the laws of physics. "This business is a constant challenge to increase capacity to meet emerging demand," Maxtor spokesman Martin Parry said. "It's a relentless cycle." For several years, hard drive manufacturers have been dramatically increasing capacity in an attempt to outdo one other. The current industry sweet spot is 20GB to 40GB drives, but Parry said the sales prospects for 100GB drives look very good. "As long as there is capacity, people will always find a way to fill it," Parry said. Until now, the highest capacity drives reached 80GB. On Monday, Milpitas, Calif.-based Maxtor also released the $229 DiamondMax D540X, an 80GB drive. Maxtor's target audience for the 100GB drives are people who want to download and save massive numbers of digital-audio files and digital images. The 100GB drive can hold 100 hours of compressed digital video or up to 25,000 four-minute digital-audio files, according to Maxtor. IDC analyst Dave Reinsel agreed that there are always people who can fill up any drive and that the group is growing, but he asserts it isn't likely that mainstream PC buyers will need that much room for storage. However, Parry asserts that, for $300, the excess capacity may be worth it to consumers anyway. The price of storage capacity, which continues to fall, has some analysts wondering whether hard drives are becoming commodity items. "There's probably more technology in a hard drive than in (the rest of) an entire PC when you consider the heads and the platters and everything," Parry responded. "We're hardly looking at pork bellies here." The new 100GB drives are a 25 percent boost over the former highest capacity, 80GB. The 25 percent increase is modest compared to the average 50 percent increases that the industry has managed to make over the last couple years. More moderate capacity increases may be a future trend as drive manufacturers get closer to the physical limits of the hardware in its current form. The limit to capacity is expected to be around 137GB, which Reinsel expects will be reached as early as this year. Maxtor expects to exceed that limit through technical advances, Parry said. He would not elaborate. Last month, IBM announced innovations that it expects will allow hard drive manufacturers eventually to reach 400GB. See also: ZDNet UK's Consumer News Section. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet news forum. Let the editors know what you think in the Mailroom. And read other letters.